The invention relates to a full caliber training projectile. Such projectile is known from German published patent application No. P 26 09 590. In this known training projectile a forward rotational symmetrical portion has an ogival shape and has a rearwardly axially extending cylindrical pin that adjoins the rotational-symmetrical front portion via a rearwardly facing annular smooth boundary surface. A ballast body is disposed rearwardly of the rotational-symmetrical front portion and the free end of the rearwardly extending pin extends into an axial central blind bore. The ballast body has a substantially full caliber dimension. The length of the rearwardly extending pin is larger than the depth of blind bore in the ballast body. The bolt has a larger exterior diameter in the forward portion thereof as compared to the region of its free end which extends into the blind bore. The interior diameter of the blind bore corresponds to the larger outer diameter in the forward region of the blind bore. In the rear region of the blind bore the inner diameter corresponds to the smaller exterior diameter of the rearwardly extending pin. In this manner, the rearwardly extending pin is firmly guided over a predetermined distance along the axis of the projectile. There is disposed a rubber elastic spring element between the rear annular surface of the forward portion and an annular boundary surface surrounding the mouth of the blind bore of the ballast body. This spring element forms a thick-walled pipe and entirely surrounds the pin and abuts against both of the front and rear boundary surfaces. The spring element is slightly sub-caliber; therefore there is present in the initial condition of the projectile a recess between both of the afore-mentioned boundary surfaces. The ballast body has a guide ring in its peripheral region.
As a result of the acceleration forces of the ballast body, which occur at firing, the rubber-elastic spring element is compressed, without the arrangement becoming over-caliber in the afore-mentioned region. As soon as the arrangement has exited from the gun barrel and no longer is under the direct influence of the propellant gases, the energy stored by the spring element is released. The ballast body is thereby slidably displaced, counter to the flight direction, on the pin towards its free end, the axial guiding is lifted, and the ballast body separates from the pin of the front portion.
Several sensitive drawbacks at the latest now appear, because the behavior of the ballast body is fully uncontrolled. In view of the fact that the ballast body separates shortly after emergence from the gun barrel from the remainder of the projectile, a dangerous condition in the vicinity of the muzzle of the gun barrel cannot be ruled out in this state of the art projectile. One only needs to observe the front portion with the rubber-elastic spring element surrounding the rearwardly extending pin. While it can not be disputed, that the mass of the remaining latter-mentioned arrangement is less than the total mass previously described, and also that the air resistance against the remaining arrangement changes as compared to that of the entire arrangement, one cannot forcibly conclude from this that a reduction of the range (of the remainder of arrangement) must occur. If finally a comparison is made between the position of the center of gravity of the mass of the entire arrangement and the position of the center of gravity of the remainder of the arrangement, then one is able to determine, that the center of gravity of the remainder of the arrangement is disposed along the longitudinal axis of the projecticle, as is the case with the center of gravity of the entire arrangement, substantially closer towards the forward end region thereof. This can lead to an overstabilization of the remainder of the arrangement and at least for the remainder of the arrangement the sought-after range reduction remains doubtful. Consequently, also the remainder of the arrangement behaves in an uncontrolled fashion at strong scattering so that also here at poor reproducability a significant risk may occur.